4QMK

Crystal structure of type III effector protein ExoU (exoU)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.5 Å
  • R-Value Free: 0.270 
  • R-Value Work: 0.206 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

A Novel Phosphatidylinositol 4,5-Bisphosphate Binding Domain Mediates Plasma Membrane Localization of ExoU and Other Patatin-like Phospholipases.

Tyson, G.H.Halavaty, A.S.Kim, H.Geissler, B.Agard, M.Satchell, K.J.Cho, W.Anderson, W.F.Hauser, A.R.

(2015) J.Biol.Chem. 290: 2919-2937

  • DOI: 10.1074/jbc.M114.611251

  • PubMed Abstract: 
  • Bacterial toxins require localization to specific intracellular compartments following injection into host cells. In this study, we examined the membrane targeting of a broad family of bacterial proteins, the patatin-like phospholipases. The best cha ...

    Bacterial toxins require localization to specific intracellular compartments following injection into host cells. In this study, we examined the membrane targeting of a broad family of bacterial proteins, the patatin-like phospholipases. The best characterized member of this family is ExoU, an effector of the Pseudomonas aeruginosa type III secretion system. Upon injection into host cells, ExoU localizes to the plasma membrane, where it uses its phospholipase A2 activity to lyse infected cells. The targeting mechanism of ExoU is poorly characterized, but it was recently found to bind to the phospholipid phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a marker for the plasma membrane of eukaryotic cells. We confirmed that the membrane localization domain (MLD) of ExoU had a direct affinity for PI(4,5)P2, and we determined that this binding was required for ExoU localization. Previously uncharacterized ExoU homologs from Pseudomonas fluorescens and Photorhabdus asymbiotica also localized to the plasma membrane and required PI(4,5)P2 for this localization. A conserved arginine within the MLD was critical for interaction of each protein with PI(4,5)P2 and for localization. Furthermore, we determined the crystal structure of the full-length P. fluorescens ExoU and found that it was similar to that of P. aeruginosa ExoU. Each MLD contains a four-helical bundle, with the conserved arginine exposed at its cap to allow for interaction with the negatively charged PI(4,5)P2. Overall, these findings provide a structural explanation for the targeting of patatin-like phospholipases to the plasma membrane and define the MLD of ExoU as a member of a new class of PI(4,5)P2 binding domains.


    Organizational Affiliation

    From the Departments of Microbiology-Immunology.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Type III secretion system effector protein ExoU
A, B
677N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
BME
Query on BME

Download SDF File 
Download CCD File 
A
BETA-MERCAPTOETHANOL
C2 H6 O S
DGVVWUTYPXICAM-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

Unit Cell:
Length (Å)Angle (°)
a = 67.218α = 90.00
b = 115.341β = 102.77
c = 88.443γ = 90.00
Software Package:
Software NamePurpose
Blu-Icedata collection
REFMACrefinement
HKL-2000data reduction
PHASERphasing
HKL-2000data scaling

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-12-17
    Type: Initial release
  • Version 1.1: 2014-12-24
    Type: Database references
  • Version 1.2: 2015-02-25
    Type: Database references
  • Version 1.3: 2017-11-22
    Type: Refinement description